This invention relates to an enzymatic process for deacylating N-acyl-6-substituted-2-substituted-1-carbadethiapen-2-em-3-carboxylic acids (I); such acylated species (I) and corresponding deacylated forms are antibiotics: ##STR1## wherein R.sup.1 and R.sup.2 are, inter alia, independently selected from the group consisting of hydrogen, substituted and unsubstituted alkyl, aralkyl, aryl, alkenyl and the like and R.sup.3 is a similarly broadly defined radical which is characterized for purposes of this process by having an amino group which bears an acyl group R.degree.. Many of such compounds I are known and available to the art. See for example, Belgium Patent No. 860,962 (filed Nov. 18, 1977). The balance of such compounds I are disclosed and claimed in co-pending, commonly assigned U.S. Patent Application Ser. No. 933,681 (filed Aug. 17, 1978) which is incorporated herein by reference.
A sub-cateogry under generic structure I includes the 6-ethyl species 1: ##STR2## R.degree. is acyl as defined above. Species 1 is known (R.degree.=acetyl) and available to the art; see the Journal of Antibiotics; Volume 31, No. 5 pages 480-482 (May 1978); such species and deacylated species are disclosed and claimed in co-pending, commonly assigned U.S. Patent Applications Ser. Nos. 933,681 (filed Aug. 17, 1978) and 861,230 (filed Dec. 16, 1977 which are incorporated herein by reference. Substrate species (genus I, above), such as 1 (above), which are isolated from fermentation broths commonly have acetyl as the acyl group (R.degree.); whereas those obtained semi-synthetically or by total synthesis are not limited to acetyl, or any other lower alkanoyl, and may have any value for the acyl group R.degree.. It is desirable to have a process for obtaining the free amino (deacylated) species, for such species usually demonstrate enhanced antibiotic activity. Also, the deacylated antibiotic may also be regarded as an intermediate for subsequent derivatization of the amino group; such derivatization processes, however, are not embraced by the present invention. As a class, whether derived from animal tissues or micro-organism, the amido acylases are effective enzymes to achieve the desired transformation. Members of the amidoacylase enzyme genus which effect the desired cleavage are given below.